The interesting case of a dual overtake.
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Sam was traveling in a compartment holding the alias S2 of a blue coloured rake. The train had departed precisely at the scheduled time but with only a dozen minutes to follow there was an unscheduled halt. To his dismay this was enough to trigger the catastrophe. At the very next station the train was looped to give way to the storm coming from behind. The red beauty roared and whipped past Sam's train within seconds. Astonished and amazed, Sam sighed and waited for an...
more... uninterrupted run ahead, given the priority his train commanded. And that's what followed too, not till long though as after some time in excess of five hours, the same storm struck Sam's train YET AGAIN and thundered past him in a moment of amazement. But HOW?
How can a train be overtook by the same train, TWICE? Well for now, Sam knows the secret. Do you?
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Besides clarifying doubts, if any, I shall respond here as and when someone comes up with correct names of BOTH the blue legend and the red beauty or by tomorrow evening 9 PM, whichever is earlier. And yes, none of the characters here is running with a delay of more than 2-3 hours nor is there any diversion/disruption/unnatural scenario.
Keep guessing. Good night.